Editor's note: Rep. Jason Chaffetz is a Republican from Utah. He is one of two members of Congress featured in CNN.com's Freshman Year series

(CNN) -- After a failed Christmas Day terrorist plot on a U.S.-bound international flight, the airline passenger screening process has received heavy scrutiny from the government, the media and the public.

Questions abound about how a Nigerian national who was supposedly on the terrorist "watch list" was able to obtain a visa, fly to the United States and transport explosive materials undetected.

The screening process at U.S. airports has received particular scrutiny in this case -- and rightfully so. Whole Body Imaging scanners being tested at many airports have the potential to detect explosives. But these invasive machines perform a virtual strip search, producing detailed images of a passenger's body.

Screeners can literally count the change in a passenger's pocket, see the sweat on his back, and view intimate gender-specific details when looking at the image.

We must carefully consider how to balance safety and security with personal privacy concerns. In the wake of an attempted attack, there is always pressure to surrender more of our liberties in the name of security. It should be our goal to employ technologies that are more effective and less invasive.

Last summer, the House passed my amendment regarding the use of WBI scanners as a primary screening device at U.S. airports. Support was overwhelming with more than 300 of my colleagues on both sides of the aisle voting in favor of the amendment permitting the use of the technology only as a secondary screening device.

The amendment, which has not yet passed in the Senate, allows the machines to be used when further screening is warranted. If a passenger sets off the metal detector, engages in suspicious behavior, or is listed on a watch list, secondary screening would be appropriate. But I oppose a blanket policy forcing every passenger to submit to a WBI scan unless WBI machines are upgraded to protect passenger privacy.

Manufacturers promise that new software addresses the privacy issues. The Dutch government is already committing to use the upgraded software. If the Dutch can successfully implement this technology, TSA should adopt it as well.

The WBI technology works. It should be available at every airport and it should be used on inbound international flights. Security personnel should be given wide discretion to use the machines for anybody with suspect behavior or whenever there is a need for secondary screening. Certainly if someone is on the terrorist watch list, requiring a WBI screening should be standard procedure.

If ever there was a case where the WBI scanning should have been used, the Christmas Day incident was it. Umar Farouk Abdulmutallab was a foreign national who was on the terrorist watch list. He is the poster child for who we should be screening with these WBI scanners.

My understanding is both airports had the scanners available, but did not use them. Abdulmutallab is certainly someone who should have gone through the full scanning process at least once, if not twice.

I'm on an airplane every three or four days. I want our airplanes to be secure as much as anyone. But it's important that we find the proper balance between the need to secure an airplane and the need to protect personal privacy.

The WBI scanner as currently deployed in the United States, while effective, is not the only tool available to us. Certainly new WBI technology is promising. But bomb-sniffing dogs also meet the threshold of more effective and less invasive. Heat-sensing technologies and puffer machines provide another less invasive screening option.

Furthermore, it's time to start profiling terrorists -- not based solely on religion, race or ethnicity, but any characteristics which repeatedly appear in terrorist profiles. Imposing further restrictions on innocent travelers is far less effective than targeting those most likely to have terrorist ties.

To the extent we can deploy less invasive technologies and still effectively secure an airplane, we should do so -- immediately.

I hope we will continue to debate where we draw the line between privacy and security. It's an important discussion to have. There are no easy answers. But I believe it is possible to preserve a measure of privacy while enhancing security on U.S. flights and I will continue fighting to achieve that goal.

The opinions expressed in this commentary are solely those of Jason Chaffetz.